Durable system for controlling the disposition of expended munitions fired at a target positioned close to the shooter

ABSTRACT

In a shooting range for training personnel in the use of firearms, a bullet trap that prevents rebounding bullets or flying debris from injuring shooters, has a central section of stacked cylindrical logs, or logs having a trapezoidal cross section, supported by stacked rectangular supporting blocks on each side. The stacked cylindrical logs have conical end sections at the end facing the shooter. These conical end sections direct incoming bullets to passageways between the cylindrical logs. Bullets passing through these passageways then strike a backstop panel. In a preferred embodiment, both the cylindrical logs and the backstop panel are made of shock-absorbing foamed fiber-reinforced concrete.

GOVERNMENT INTEREST STATEMENT

[0001] The invention described herein may be manufactured, licensed andused by or for governmental purposes without the payment of anyroyalties thereon.

I. BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates to a bullet trap that includes a screenthat protects persons at a firing range from being struck by reboundingbullets or flying debris generated by the impact of bullets.

[0004] 2. Prior Art

[0005] Bullet screens and traps used on firing ranges are known to theart. U.S. Pat. No. 4,821,620 discloses an anti-spatter screen made ofrubber-like material adapted to self-closing is secured to the frontface of a deflector plate. U.S. Pat. No. 5,564,712 discloses a bullettrap for indoor shooting with small arms using a vertically-suspendedrubber curtain and a vertically-suspended steel impact plate. U.S. Pat.No. 5,486,008 describes a bullet trap having a passageway between upperand lower boundary walls converging on a deceleration chamber. U.S. Pat.No. 5,718,434 discloses a bullet trap for pistol and rifle ranges havingone or more deflecting plates having curved sections which directbullets toward a back wall and a final impact plate. U.S. Pat. No.5,988,647 describes a projectile trap having three groups of suspendedpolyurethane sheets in which these sheets have increasing hardness as abullet traverses them.

[0006] The present invention relates to a bullet trap which is durableand nonflammable, and which allows a shooter to practice safely at closerange. The bullet screen of the bullet trap in accordance with thisinvention is more durable than conventional bullet screens using woodand elastomers, which deteriorate quickly after repeated shots, andwhich may be set on fire when certain munitions are fired. The bullettrap of this invention has conical heads that guide bullets intopassageways that traverse the bullet screen.

II. SUMMARY OF THE INVENTION

[0007] The bullet trap of this invention serves to confine reboundingbullets and flying debris generated by bullet impacts, preventing themfrom traveling to the area where personnel are stationed during shootingexercises. The bullet trap is placed behind a target and in front of abullet-absorbing backstop panel.

[0008] The bullet trap of this invention consists of a bullet screensupported by blocks on each side, as described more fully below. Thebullet screen consists of cylindrical logs having conical heads at oneend, stacked such that their circular cross sections are on square orequilateral triangular centers and their conical heads are pointingtowards incoming bullets. The square or triangular stacking of thecylindrical logs provides passageways along the sides of the logs intowhich bullets are directed. Alternatively, the logs may be trapezoidalin cross section and be stacked in such manner as to provide passagewaysfor the passage of bullets along the sides of each log. The ends of thelogs, in this alternative configuration, are formed to have achisel-like shape and face incoming bullets.

[0009] The stacked logs are held in place by stacks of rectangularblocks (herein referred to as supporting blocks) on both sides of thelogs. The conical heads, or chisel-shaped ends as the case may be, guidebullets approaching the bullet screen towards the passageways thattraverse the bullet screen as a result of the square or triangularstacking of the cylindrical logs. In-coming bullets strike the conicalheads of the logs at a low angle and ricochet into the passagewaysbetween the logs. Bullets may make several more low-angle ricochetingimpacts on the sides of the conical heads of the logs before traversingthe screen and impacting on the bullet-absorbing backstop panel. Whenlogs having trapezoidal cross sections are used, bullets makecorresponding contact with the chisel-shaped heads having taperedfaceted faces and have the same effect as the conical heads. Thenarrowness of the passageways between the logs and the limited kineticenergy or momentum of the rebounding debris virtually eliminate thepossibility of any bullet or any debris returning to the shooters'station.

[0010] An advantage of the bullet trap of this invention, in a preferredembodiment, is that the bullet screen logs are made of shock-absorbing,foamed, fiber-reinforced concrete. This concrete may contain a slightexcess of calcium hydroxide which, when exposed to rain and moisture inthe field, produces a slightly alkaline leachate that reduces the amountof heavy-metal contamination leaving the range, e.g., lead contaminationthat may result from the firing of lead bullets. Furthermore, in thispreferred embodiment, the trap does not require any preservative orcoating to prevent rotting or insect attack, and therefore has lowmaintenance requirements. The concrete bullet trap of this preferredembodiment may be used with tracer, incendiary, or deflagratingammunition without fire hazard. Other materials such as wood orelastomers may be used in building bullet traps where fire hazards arelow and durability is of secondary importance.

III. BRIEF DESCRIPTION OF THE DRAWINGS

[0011]FIG. 1 is a schematic diagram showing the placement of the bullettrap with respect to the shooter, target, and backstop panel. FIG. 2shows a view of the bullet screen including supporting blocks.facing theshooter. FIG. 3 shows a side view illustrating the stacking ofcylindrical logs used in building the bullet screen.

IV. DETAILED DESCRIPTION OF THE INVENTION

[0012] With reference to FIG. 1, a shooter 1 shoots a bullet whichpasses along a bullet trajectory 2 and strikes and penetrates a target3. The bullet continues along its trajectory and strikes a bullet screen4. The bullet may become embedded in the material of the bullet screenor, more likely, penetrate it by passing through passageways created bythe shape of the stacked bullet screen logs. After the bullet penetratesthe screen 4, it travels on and strikes a backstop panel 5. At thispoint, the bullet and any flying debris that may have been dislodgedfrom the backstop panel 5 have insufficient momentum to rebound andre-penetrate the screen while traveling in the opposite directiontowards the shooters. The bullet and any debris will fall to the bottomof the space between the screen 4 and the backstop panel 5.

[0013]FIG. 2 shows a front view of the bullet screen 4, which is made ofcylindrical logs 6 stacked on top of each other.such that their circularcross-sections are on square or equilateral triangular centers and theirconical heads 8 are pointing towards incoming bullets. The square ortriangular stacking of the cylindrical logs 6 provides passageways 9along the logs. The cylindrical logs 6 are held together by large,preferably rectangular, supporting blocks 7 on both sides 10 of thestack of cylindrical logs 6. The supporting blocks 7 are piled to aheight sufficient to support the height of the stacked screen logs.

[0014] Typical dimensions of the cylindrical logs are: diameter, 6″ (15cm); length of cylindrical portion, 3 ft (90 cm); length of conicalportion, 1 ft (30 cm). It is to be understood that these dimensions aretypical but not limiting. Shock absorbent material used in making thelogs for the screen 4, preferably, is foamed, fiber-reinforcedshock-absorbent concrete (SACON) weighing, typically, 90 lbs. per cubicfoot (1.4 grams per cubic centimeter). The diameter of cylindrical logs,typically, is about 6″ (15 cm). Each log weighs about 60 lbs. Bulletscreens of this type can be used with weapons up to 0.50 caliber (12.7mm). As noted, they can be used with tracer, incendiary, anddeflagrating bullets without risk of igniting the screen.

[0015] The supporting blocks 7 holding the stacked bullet screen logs 6in place may be wooden boxes filled with sand, or SACON which maycontain a slight excess of calcium hydroxide, as described above which,when exposed to rain and moisture in the field, produces a slightlyalkaline leachate that reduces the amount of heavy-metal contaminationleaving the range, e.g., lead, that may result from the firing of leadbullets.

[0016] The dimensions of an installed bullet trap, typically, are asfollows: width of the bullet screen, 8 ft (2.4 m); height of the bulletscreen, 8 ft (2.4 m); and depth of 4 ft (1.20 m). including the conicalheads. The width of the supporting blocks 7 for retaining the bulletscreen is 2 ft (60 cm) on each side of the bullet screen; the height ofthe blocks is 2 ft (60 cm); the length of the blocks 7 is 3 ft (90 cm).A firing range 8 ft. high would have supporting blocks stacked fourblocks high. It is to be understood that these dimensions are typicalbut not limiting.

[0017] It will be understood that the foregoing description of preferredembodiments of the present invention is for purposes of illustrationonly, and that the various structural and operational features hereindisclosed are susceptible to a number of modifications and changes, noneof which entail any departure from the spirit and scope of the presentinvention as defined in the following claims.

What we claim is:
 1. A bullet trap for confining bullets and flyingdebris resulting from bullet impact comprising: (a) a bullet screencomposed of a plurality of cylindrical logs, each having a conical headat one end thereof, said logs being stacked such that the conical headsface incoming bullets; (b) said stacked cylindrical logs formingpassageways between them to provide passage for bullets through thebullet screen; and (c) supporting blocks for retaining the stackedcylindrical logs on two opposing sides thereof.
 2. The bullet trap ofclaim 1 wherein the logs are made of shock-absorbing material.
 3. Thebullet trap of claim 1 wherein the supporting blocks are made ofshock-absorbing material.
 4. The bullet trap of claim 2 wherein theshock-absorbing material is fiber-reinforced foamed concrete.
 5. Thebullet trap of claim 4 wherein the fiber-reinforced foamed concretefurther comprises calcium hydroxide.
 6. The bullet trap of claim 3wherein the shock-absorbing material is fiber-reinforced foamedconcrete.
 7. The bullet trap of claim 1 wherein the supporting blocksare stacked rectangular blocks.
 8. The bullet trap of claim 7 whereinthe rectangular supporting blocks are wooden boxes filled with sand. 9.The bullet trap of claim 1 further comprising a bullet-absorbingbackstop panel disposed behind the bullet screen.
 10. A bullet trap forconfining bullets and flying debris resulting from bullet impactcomprising: (a) a bullet screen composed of a plurality of logs havingtrapezoidal cross sections, each log having a tapering faceted head atone end thereof, said logs being stacked such that the tapering headsface incoming bullets; (b) said stacked logs forming passageways betweenthem to provide passage for bullets through the screen; and (supportingblocks for retaining the stacked cylindrical logs on two opposing sidesthereof.11. The bullet trap of claim 10 wherein the logs are made ofshock-absorbing material.12. The bullet trap of claim 10 wherein thesupporting blocks are stacked rectangular blocks.